Method for mixing molten metal



Aug. 5, 1969 R. a. wuzmm ET AL 3,459,536

METHQD FOR MIXING MOLTEM METAL Original Filed Nov. 6. 5 Sheets-Sheet 1 \J.. .Ci,

INVENTORS ROBERT E TOUZALIN RUDOLPH R. PATRlCK r r" L/ML M I M ATTORNEYS Aug. 5, 1969 R. E TOUZALlN ETA!- 3,

I METHOD FOR MIXING MOLTEN METAL Original Filed Nov. 6, 1964 5 Sheets-Sheet 2 wi l: "715.1 1 I INVENTORS ROBERT E TOUZALIN RUDOLPH' R PATRICK 44 .1141 ['Mn/ ATTORNEYS Aug. 5, 1969 R. TOUZALIN ET AL 5 ,53

METHOD FOR MIXING MOLTEN METAL Original Filed Nov. 6, 1964 5 Sheets-Sheet 3 INVENTORS ROBERT Ev TOUZALIN RqooLPH R. PATRICK ATTORNEYS Aug. 5, 1969- R. E. TOUZALIN ET AL 3,459,536

. METHOD FOR MIXING MQLTEN METAL 7 Original Filed Nbv. a, 1964 s Sheets-Sheet 4 INVENTORS ROBERT E. TOUZALIN RUI'JOLF'H R. PATRICK ATTORNEYS Aug. 5, 1969 R. E. TOUZALIN ET AL 3,4 5

mamon mm mxme MOL'I'EN METAL Original Filed Nov. 6, 1964 5 sheeis -sheet 5 w mvewroas ROBERT E. TOUZALIN BYRUOOLPH a. PATRICK ATTORNEYS United States Patent US. CI. 75-45 Claims ABSTRACT OF THE DISCLOSURE A method for adding and mixing additive materials with molten metal in a ladle. The steps including mixing the molten metal by rotating an impeller mechanism, selectively regulating the rate of rotation of the impeller mechanism to cause a vortex to be formed in the molten metal, and feeding an additive material into the vortex for uni formly mixing the additive material with the molten metal.

This invention relates in general to mixing apparatus, and more particularly to a mixing apparatus for use in connection with the mixing of relatively large batches of liquid-like materials. The present application is a division of pending application Ser. No. 409,393, filed Nov. 6, 1964, now Patent No. 3,313,528.

In industry today it is oftentimes necessary to mix relatively large batches of liquid-like material, such as chemicals or molten metals. Many times it is necessary to introduce additive ingredients into a batch of the liquidlike material, for the purpose of providing a particular analysis for the material. This addition of ingredients should be carried out in a manner so that the ingredients will be mixed uniformly throughout the mass of material, and this thorough mixing of a relatively large mass of material, often at a relatively high temperature, is extremely difficult to accomplish.

The present invention provides a novel method for mixing a relatively large batch of liquid-like material, and which will expeditiously mix the batch, so that any analysis of the same will be substantially uniform throughout the entire batch.

Accordingly, an object of the present invention is to provide a novel method for mixing relatively large batches of liquid-like material.

Another object of the invention is to provide a novel method which will expeditiously mix a relatively large batch of material, and which will expedite the mixing of additives to the batch.

A still further object of the invention is to provide a novel mixing method which causes a strong vortex at the centerof rotation of an impeller, and which acts to draw additives provided down into the molten mass.

Other objects and advantages of the invention will be apparent from the following description taken in conjunction with the accompanying drawings wherein:

FIG. 1 is a side elevational, partially sectioned view of a mixing apparatus in a working position for carrying out the method, the fragmentary phantom lines show a raised or non-working position of the carriage of the mixer mechanism;

FIG. 2 is an enlarged, elevational view of the impeller frame and rod construction, with the refractory sleeves of the impeller removed;

FIG. 3 is an enlarged, fragmentary elevational view taken from the right hand side of FIG. 2, and showing the connection of the socket and associated impeller rod to the impeller frame;

FIG. 4 is an enlarged, fragmentary exploded view of the upper end of the socket connection of one of the impeller rods, and showing the arrangement for connecting the rod to the socket;

FIG. 5 is an enlarged, fragmentary, vertical sectional view of the bottom end of the impeller rod and the refractory sleeve members mounted thereon;

FIG. 6 is an enlarged, partially sectioned, elevational view of the impeller mechanism illustrating a modified embodiment thereof, and more particularly one having a feed hopper associated therewith;

FIG. 7 is a sectional plan view taken generally along the plane of line 77 of FIG. 6, looking in the direction of the arrows;

FIG. 8 is a sectional view taken generally along the plane of line 8-8 of FIG. 6, looking in the direction of the arrows;

FIG. 9 is an enlarged, sectional view showing the connection of the impeller rod and its associated socket to the impeller frame of the FIG. 6 arrangement;

FIG. 10 is an enlarged, elevational view of another embodiment of impeller unit having a feed hopper mechanism associated therewith;

FIG. 11 is an elevational view taken from the right hand side of FIG. 10;

FIG. 12 is a sectional view taken generally along the plane of line 1212 of FIG. 11 looking in the direction of the arrows;

FIG. 13 is a fragmentary, elevational view of another embodiment of impeller mechanism, and one which generally combines the features of FIG. 6 with those of FIGS. 10 and 11;

FIG. 14 is a sectional view taken generally along the plane of line 1414 of FIG. 13.

Referring now again to the drawings there is shown a ladle car 10 including a refractory ladle 12 with preferably a removable cover 14 thereon, which may have an opening 14a therein, through which the impeller mechanism 16 may be lowered, for stirring of a liquid-like mass of material, such as for instance a batch of molten iron. The ladle car may be mounted on wheels 18 for rolling movement along the tracks 18a, and in the conventional manner.

A vertical bearing column 20 may be provided, with column 20 being preferably mounted for rotation about a generally vertical axis by means of upper and lower bearing structure 22, 22a. Bearing structure 22 may be supported by an overhead support 24, and bearing structure 22a may be supported on footing 24a.

Rotation of the column 20 about its vertical axis may be accomplished by means of a double-acting, fluid powered motor unit 26, rotatably supported from an upper support 26a, and pivotally coupled to an arm 28 which in turn may be coupled to the column. Thus upon actuation of the motor unit 26, column 20 will be rotated in its bearings 22, 22a. The arrangement is preferably such that the column 20 may be rotated at least so that the mixer mechanism can be moved into and out of alignment with'the ladle 12, when the mixer is raised from its position within the ladle.

A generally laterally extending carriage 30 is mounted on the column 20 preferably for vertical movement with respect thereto, and as for instance by means of wheel members 32 mounted on the carriage and coacting with flanges or tracks on the column 20. Downward movement of the carriage 30 with respect to the column 20 may be limited by means of stops 34 on column 20.

Vertical movement of the carriage 30 carrying the impeller mechanism may be accomplished by providing a powered hoist 36, mounted on column 20 adjacent its upper end, with the hoist 36 being operatively connected to the carriage 30 by means of preferably metal or wire cables 38, coacting with the rotatable pulley 39, mounted on arm 40 which may be pivoted as at 40a to the carriage 30. Thus upon actuation of hoist 36 and reeving of the cable 38, the carriage 30 may be moved to an upper POSI- tion, as shown in phantom lines in FIG. 1.

A gear housing 42 may be mounted adjacent the distal end of carriage 30, and such housing may enclose a geared speed reduction unit 44, driven by means of shaft 46 operably coupled to a fluid powered motor unit 48 mounted on the carriage 30. Motor unit 48 may be coupled by flexible hose 50, preferably of metal, to a source of actuating fluid. Reduction unit 44 drives a vertical shaft 52 which in turn is coupled by means of a preferably split coupling 52a to the impeller mechanism 16. A plate-like heat shield 53 (FIG. 1) may be provided to aid in protecting the reduction unit and carriage.

Impeller mechanism 16 may comprise a frame including a body portion 55 (FIGS. 1 and 2) which may be of the fabricated, generally elongated box-like construction illustrated in FIGS. 2 and 3, with the split coupling section 52b extending upwardly therefrom, for connection to the drive shaft 52 of the reduction unit 44. Depending from body portion 55 adjacent opposite ends thereof and secured thereto as by welds may be a pair of socket members 58, which in turn may be connected by a longitudinal web 58a. Sockets 58 are disposed obliquely with respect to body portion 55 as best shown in FIG. 2, and may also have strengthening webs 60 coacting between the sockets and the body portion for strengthening the attachment of the sockets to the body portion.

Each of sockets 58 mounts an elongated impeller arm or rod 62, with the rod, in the embodiment illustrated, having a head 62a at its distal end. The rod 62 also has a tapered slot 64 therethrough (FIG. 4) adjacent its upper end which is adapted for general alignment with a complementary slot 65 through the walls of the respective socket member 58, for receiving therein a tapered pin 66 (FIG. 4) for detachably connecting the rod to its respective socket.

Each of the rods or arms is adapted to receive thereon in supporting relation a covering or sleeve 70 of heat resistant material. The sleeves 70 may be formed of graphited-refractory material and are preferably of the sectional, cylindrical configuration illustrated. A preferably refractory nut 72 can be slipped over the upper end of the rod and then threaded into the refractory tip segment 74 of the sleeve, and then the other sleeve sections 76 may be slipped over the end of the rod into the superimposed condition illustrated in FIG. 5. The sleeve sections preferably have complementary embossments and recesses 75, 75a thereon for aiding in aligning the sleeve segments and aiding in maintaining their assembled relation on the respective rod. The refractory sleeve sections 76 preferably have a refractory cement placed between their joints for sealing the latter, and may be held on the rod by spring members 78 (FIG. 1) coacting between the adjacent sleeve section and the underside of the associated socket 58. Asbestos rope is preferably wound about springs 78 after assembly to aid in protecting the springs.

It will be seen that the wedge 66 can be readily removed from the associated slots in the rod 62 and socket 58, thereby permitting removal of the rod from its socket and ready replacement of the refractory sleeves.

When the motor unit 48 is actuated to cause rotation of the drive shaft 52 and thus rotation of the associated impeller mechanism 16, a highly effective mixing action of the liquid-like batch of material in the ladle 12 occurs, with an intense agitation of the batch of material and the forming of a strong vortex at the center of the batch. This agitation and strong vortex draws additives which are added to the ladle as by means of chute 80, down into the molten batch, thus causing a higher recovery of the additives furnished thereto and a more uniform analyses of the batch of material. It will be noted that the impeller rods and associated sleeves are of a quite long dimension, and preferably extend a substantial distance into the batch i B of material. The refractory sleeves on the impeller mechanism have the ability to withstand high temperatures so that the impeller can be used for numerous mixing cycles. Also such refractory sleeves are low in cost and with the arrangement illustrated are readily replaceable on the associated rod 62 if and when replacement becomes necessary.

Referring now to FIG. 6 there is shown a modified form of the invention wherein a feed hopper is integrally associated with the mixing apparatus for expeditiously adding additives to the batch of material, and tothe center of the vortex formed by the rotary impeller mechanism. In this arrangement, the split coupling section 52b has a tubular-like, in the embodiment illustrated, depending support member 82, which supports thereon an inverted conical-like hopper 84. Webs or blades 86, 86a extend generally radially between the tube 82 and the inner surface of the hopper 84, for supporting the hopper on the tube 82. Webs 86, 86a are preferably disposed obliquely with respect to the vertical, and as best shown in FIG. 7, with webs 86a being offset with respect to the webs 86 when viewed in plan. The oblique relationship of webs 86, 86a provides for optimum mixing by the blades, which engage the material being added by means of a chute or tube 80, and cause it to be more uniformly mixed and distributed as it is flowing into the ladle 12. Hopper 84 preferably has generally cylindrical lower section 88 for directing a generally downwardly directed stream of the additive materials into the vortex formed by the rotating impeller mechanism.

Oblique sockets 58 which support the rods 62 therein, are of a generally similar construction as the sockets 58 of the first described embodiment, and with such sockets 58' being connected to the outer surface of the hopper 84 by means of upper webs 90 and lower lateral webs 92. Cross web 96 may also be provided for further strengthening the attachment of the sockets to the hopper 84.

Referring now to FIG. 9, it will be seen that the slot 64' through the associated rod 62 is adapted to be generally aligned with the slot 65' in socket 58'. However, the arrangement is preferably such that the key 66 coacts with the upper edge of the slot 64' in the rod 62, and with the lower edge of the slot 65' in the socket 58'. A cotter pin 97 may be provided through the wedge 66 to positively hold it in assembled relationship. There is also preferably provided a slot 98 in the associated web 90 which registers with a complementary slot 99 in the upper end of the respective socket 58' for aiding in removal of the rod from its associated socket for replacement of the refractory sleeves.

It will be seen that upon rotation of the drive shaft 52 is driven by shaft 46 of the motor unit, the support member 82 will rotate, thus causing rotation of the hopper 84 and associated impeller mechanism and that the additive material being added by means of chute 80 will be mixed and rotated in the hopper 84, due to its rotation and the striking of the material by the rotating mixer blades 86, 86a. The additive material will then be directed downwardly through cylindrical section 88 to the center of the vortex formed by the rotating impeller 16, resulting in highly effective mixing and additive adding operation. Hopper 84 may rotate, for instance, at a speed of approximately 100 r.p.m. and may be varied in its speed of rotation by the provision of conventional variable speed controls in the system controlling the actuation of motor 48.

Referring now to FIGS. 10, 11 and 12, there is shown a further modification of the invention wherein the impeller rods or arms are crossed with respect to one another instead of extending diagonally outwardly when viewed in side elevation, and as shown for instance in FIG. 10. The sockets 58" of this arrangement may be of the same general construction as those of the FIG. 6 embodiment, and are secured to upper and lower generally horizontal retainer plates 100, 100a, which in turn are attached as by welds to the exterior surface of the hopper 84. As can be seen from FIGS. and 11, such socket members are directed downwardly and inwardly with respect to one another, and with respect to the hopper 84, so that when the rods and associated sleeves are attached thereto, the latter cross one another, with the cylindrical section 88 of the rotatable hopper extending between such impeller arms. Webs 101 extending between and secured to the top retainer plate 100 and the exterior wall of the hopper strengthen the attachment of the socket members 58" to the hopper, while retainer Webs 102 extending between and secured to the socket members 58" and to the exterior of the hopper, and disposed intermediate the retainer plates 100, 100a, further strengthen the attachment of the sockets to the hopper. It has been found that such crossed elongated impeller arms causes highly intense agitation of a mass of liquidlike material, such as molten metal, with an extremely strong vortex at the center thereof which draws additives flowing from a chute 80 down into the vortex, and then mixes it uniformly throughout the batch in the ladle 12.

Referring now to FIGS. 13 and 14 there is shown a further embodiment of the invention wherein the generally inverted U-shaped arrangement of impeller arms as shown for instance in FIGS. 6 to 8 is combined with the crossed arrangement of impeller arms, as shown for instance in FIGS. 10 to 12, to provide a mixer arrangement comprising four impeller arms effectively and symmetrically attached to the rotatable hopper 84, and which effectively provides for mixing of additives to the liquidlike mass of material in a ladle. It will be seen that with such an arrangement there is no interference between any of the parts of the impeller arms, and the liquidlike material is effectively mixed with an extremely strong vortex caused in the center of the batch during the mixing operation.

From the foregoing discussion and acompanying drawings it will be seen that the invention provides a novel method of mixing large batches of liquid-like material, such as for instance molten metals, chemicals, etc., and in a manner that the ingredients will be mixed uniformly throughout the mass of material, and which will operate effectively at relatively high temperatures. The invention also provides a novel method for more uniformly distributing additives to the molten mass throughout the molten mass. The invention also provides a novel method for mixing a large batch of material and adding additives thereto.

The terms and expressions which have been used are used as terms of description, and not of limitation, and there is no intention in the use of such terms and expressions of excluding any equivalents of any of the features shown or described, or portions thereof, and it is recognized that various modifications are possible within the scope of the invention claimed.

We claim:

1. A method for adding and mixing additive materials with a relatively large batch of molten metal in a ladle, the steps comprising, introducing molten metal into a ladle, mixing the ;molten metal in the ladle by rotating an impeller means supported above and extending into said ladle, selectively regulating the rate of rotation of said impeller means to cause a vortex to be formed in said molten metal, and swirling said additive material above said molten metal, said swirling action including simultaneous rotation and mixing of said additive material, and thereafter introducing said additive material generally centrally into said vortex.

2. A method in accordance with claim 1, including the step of regulating the rate of the swirling action of said additive material.

3. A method in accordance with claim 1, wherein said molten metal is a ferrous metal.

4. A method for adding and mixing additive materials with a relatively large batch of molten ferrous metal in a ladle, the steps comprising, introducing said molten metal into a ladle, mixing the molten metal by rotating an impeller mechanism supported above and extending downwardly into the ladle and below the surface of the molten metal therein, selectively regulating the speed of rotation of said impeller mechanism to cause a vortex to be formed centrally of and within the molten metal, and swirling an additive material generally into the center of said vortex by rotating a hopper supported above the molten metal for uniformly mixing the additive material with said molten metal.

5. A method in accordance with claim 4, including the step of simultaneously mixing the additive material in said hopper during rotation of said hopper.

References Cited UNITED STATES PATENTS 2,528,514 11/1950 Harvey et al 259-4 X 2,653,801 9/1953 Fontein et a1. 259-4 2,724,580 1 1/ 1955 Revallier 259-4 3,246,883 4/1966 Ashbrook 259-4 1,866,668 7/1932 Protzeller et al 61 X 2,129,445 9/1938 Rehns 7593 X 2,260,226 10/ 1941 Kirkham 7593 X 2,786,755 3/1957 Paddock et al 75135 X 3,272,619 9/1966 Sweeney et al 75l35 X 3,339,897 9/1967 Davis 25924 X 3,378,235 4/1968 Udy et al 259-24 X FOREIGN PATENTS 1,094,231 12/ 1954 France. 1,366,804 6/ 1964 France.

L. DEWAYNE RUTLEDGE, Primary Examiner HENRY W. TORRING II, Assistant Examiner U.S. Cl. X.R. 

